Added DataScript Query Browser

Right. The usual way of handling this kind of setup is to do any db/API calls in `will-mount` of the component. You can use `om/transact!` here and once the data is fetched the component will be rendered with that data. I did something like this here https://github.com/annapawlicka/om-data-vis/blob/master/examples/chart-http/src/core.cljs#L44